An electrode material is disclosed in Patent Literature 1 which is an activated carbon with an average particle size of 20 to 30 μm and consists of an activated carbon (A) having voids of 1 nm to 30 nm in a particle and a porous carbon (B) with an average particle size of 0.1 to 20 μm, where the porous carbon (B) is inserted into a gap between particles created by the activated carbons (A). In addition, a carbonaceous material is disclosed in Patent Literature 2 in which a micropore volume is 10 to 60% of the total pore volume, a mesopore volume is 20 to 70% of the total pore volume, and a macropore volume is 20% or less of the total pore volume, wherein the total pore volume is 0.3 cm3/g to 2.0 cm3/g and the total specific surface area is 1000 to 2500 m2/g.